An Historical Account of the Origin and Progress of Astronomy: With Plates Illustrating, Chiefly, the Ancient SystemsBaldwin and Cradock, 1833 - 520 Seiten |
Im Buch
Ergebnisse 1-5 von 57
Seite 100
... computed . Whether the Egyptians determined the length of the year by the heliacal risings of stars , or by the occurrence of the equi- noxes or solstices ; while they continued to use that which was denominated the sacred year , and ...
... computed . Whether the Egyptians determined the length of the year by the heliacal risings of stars , or by the occurrence of the equi- noxes or solstices ; while they continued to use that which was denominated the sacred year , and ...
Seite 111
... computed from the cycle . The coincidence is certainly remarkable , and may prove that the period has been formed by a comparison of the mean motions of the sun and moon ; but , while the antiquity of the Hindu tables is liable to so ...
... computed from the cycle . The coincidence is certainly remarkable , and may prove that the period has been formed by a comparison of the mean motions of the sun and moon ; but , while the antiquity of the Hindu tables is liable to so ...
Seite 113
... computed from them are corrected from time to time , as observations are multiplied and become more perfect , and no correction of an empirical nature is now admitted . * Astron . Ancienne Eclairciss . lib . VIII . sect . 15 . Hitherto ...
... computed from them are corrected from time to time , as observations are multiplied and become more perfect , and no correction of an empirical nature is now admitted . * Astron . Ancienne Eclairciss . lib . VIII . sect . 15 . Hitherto ...
Seite 212
... computed will be expressed in terms of E M , but the diameter hk of the earth being supposed to be known , it is evident that , by propor- tion , the values of those dimensions may be found in stadia or any other measures of length . We ...
... computed will be expressed in terms of E M , but the diameter hk of the earth being supposed to be known , it is evident that , by propor- tion , the values of those dimensions may be found in stadia or any other measures of length . We ...
Seite 214
... compute the radius of the eccentric orbit and the position of its centre , or the pro- portion between the radii of the homocentric circle and the epicycle ; and it is impossible to doubt that the deductions of theory were compared with ...
... compute the radius of the eccentric orbit and the position of its centre , or the pro- portion between the radii of the homocentric circle and the epicycle ; and it is impossible to doubt that the deductions of theory were compared with ...
Andere Ausgaben - Alle anzeigen
Häufige Begriffe und Wortgruppen
according Almagest ancient angle apogeum appear apsides Arabians ascertained ascribed assigned astronomer attraction axis Bailly cause celestial bodies centre Chaldeans Christ circle circumference coincide comets commencement computed consequently considered constellation Copernicus degrees described determined diameter direction earth eccentric ecliptic Egypt Egyptians elements epicycle epoch equal equator equinoctial points equinox Eudoxus fixed stars formed former gnomon Greeks heavens heliacal heliacal rising Hindus Hipparchus horizon hypothesis inequalities inferior planets instruments interval Jupiter Kepler known latitude latter length longitude luminary lunar mean distance mean motion mentioned Mercury meridian moon's movements nearly Newton nodes obliquity observations obtained opinion orbit parallax period phenomena philosopher planetary planets Plutarch pole precession probably Ptolemy respect retrograde revolution revolve right ascension rising Saturn shew shewn sidereal solar solstice sphere sun and moon sun's superior planets supposed surface theory tion Tycho Brahe variations velocity Venus vernal equinox zodiac
Beliebte Passagen
Seite 500 - A prodigious number of physical phenomena are perceived to follow as necessary consequences from Newton's grand law, that bodies tend toward each other with a force varying inversely as the square of the distance and directly as the mass of the bodies. But we should reach a higher unity and obtain a deeper insight into nature did we know not merely the empirical fact that bodies do so, but the cause why they do so. It is this which incites in the rational physicist the desire to find out the cause...
Seite 30 - Who knows exactly, and who shall in this world declare, whence and why this creation took place ? The gods are subsequent to the production of this world: then who can know whence it proceeded ? or whence this varied world arose ? or whether it uphold [itself], or not ? He who, in the highest heaven, is the ruler of this universe, does indeed know; but not another can possess that knowledge.
Seite 512 - ¡mother, and so contrary to the ideas which had been formed respecting the figure of the terrestrial globe, would seem to indicate great irregularity ; and as there can be little doubt of the accuracy of...
Seite 102 - A solar day is the interval between two successive returns of the sun to the same meridian. The sun moves through 360 degrees of longitude in one tropical year, or 365 days, 5 hours, 48 minutes, and 47 sec« onds. Hence the sun's mean daily motion in longitude is found by the proportion One year : one" day : : 360° : 59
Seite 100 - ... so far as we know, be independent of every other ; for it is only in virtue of each being supposed to be an ultimate property or to point to an ultimate property that it has any claim to be taken into the account. Thus, if any two of the properties are found to be joint effects of the same cause or to stand to each other in the relation of cause and effect, they furnish only one argument instead of two.
Seite 93 - Die iam illustri signum e tabernaculo regis bucina dabatur. Super tabernaculum, unde ab omnibus conspici posset, imago solis crystallo inclusa fulgebat.
Seite 20 - Heliadse, or children of the sun (that is, men from the East), excelled all other men in knowledge, particularly in the knowledge of the stars. One of this race, named Actis (a ray), built Heliopolis, and named it after his father, the sun. Thenceforward the Egyptians cultivated astrology with so much assiduity as to be considered its inventors. On the other hand Tatius says that the Egyptians taught the Chaldaeans astrology.
Seite 405 - The knowledge which man had acquired of the visible heavens received many important accessions from the discoveries which Galileo was enabled to make by means of the telescope. Except the sun and moon, not one of the celestial bodies had hitherto been observed to have any visible form or magnitude, and it was to the eye of reason alone that those appeared to be anything but plane surfaces : the fixed stars and the...
Seite 406 - ... of form ; while the fixed stars appeared unchanged, or only divested of the radiance with which they seem to be surrounded when seen by the naked eye ; and hence it became obvious that the former must constitute a distinct group of bodies infinitely nearer the earth than the others. The sun, from the spots observed on his surface, was found to revolve on its axis, and consequently was ascertained to be globular; and the light and dark spaces on the moon were distinctly perceived to be mountains...
Seite 64 - ... varias ipsa lucis mutationes habet ; atque etiam tum subiecta atque opposita soli radios eius et lumen obscurat, tum ipsa incidens in umbram terrae, cum est e regione solis, interpositu interiectuque terrae repente deficit.